The leaders of the United Mine Workers of America (UMWA) and the International Brotherhood of Electrical Workers (IBEW) recently sent a letter to the co-sponsors of the Green New Deal opposing the idea. “We will not accept proposals that could cause immediate harm to millions of our members and their families,” they wrote, even as they said they agreed that “doing nothing is not an option” on climate The Green New Deal has the potential to unify the labor and environmental movements by creating good jobs to fight climate change. The proposal could be the most significant development in labor organizing in a generation. It could also protect workers in vulnerable industries from disruptive transitions away from fossil fuels. Yet some unions appear more concerned about preserving fossil fuel jobs than with preventing a global calamity. This is a fundamentally shortsighted choice—for workers, for organized labor, and for the planet. The worldwide scientific...